PVC blending throughput boosted by 50%

Edited by the Engineeringtalk editorial team Mar 6, 2002

The PVC blending plant of Dolphin Division of Sealed Air Corporation has increased production throughput by up to 50% following a plant upgrade undertaken by Advanced Bulk Systems.

The PVC blending plant of Dolphin Division of Sealed Air Corporation has increased production throughput by up to 50% following a plant upgrade undertaken by bulk handling specialists Advanced Bulk Systems.

The plant, formerly known as Dolphin Packaging, is located at Poole in Dorset and produces rigid PVC film or sheet up to 1mm thick which is thermoformed into semirigid containers.

The end products are typically food tubs, trays and pots etc, but can also be used for a wide range of POS packaging or display containers in other markets.

A fully automatic batching and mixing system, which had been considered state-of-the-art when commissioned in the late 1980s, had started to become unreliable and required frequent maintenance.

The later addition of a second downstream process line had also exacerbated problems, with the system unable to cope with production demands to feed two machines.

Outsourcing of ready-mixed compounds to compensate for the shortfall also incurred additional costs of several thousand pounds per week.

Advanced Bulk Systems initially produced a functional design specification (FDS), which was produced in close consultation with Dolphin production and engineering teams.

Their aim was to decrease system processing times and at the same time increase the overall efficiency of the existing conveying and batching to and from the mixer/cooler unit.

As PVC production on site was a 24 hour operation, it was essential that downtime was minimised.

A temporary modification carried out by ABS ensured that production was maintained while major plant alterations were undertaken.

All work had to be carried out within only a two week window of availability.

This included mechanical work of modifying and upgrading silo discharge systems, pneumatic conveying equipment and associated air movers, together with valving, vacuum weigh hoppers and loadcells.

To ensure full utilisation of this work, the existing control system was replaced with a modern PLC driven SCADA software package, incorporating full management and control of product formulations and plant alarms with data reports on stock control and quality checks.

All work was completed on time and the plant has been operating at much higher levels of production without any major problems.

Malcolm Smith, chief engineer for Dolphin comments: "We now have more product consistency and greater plant efficiency backed-up with a more reliable and transparent windows based operating software which can be easily operated and updated by our own personnel.

Advanced Bulk Systems met all our requirements and successfully minimised the crucial downside element of the whole operation.

Our subsequent savings on maintenance, lost production, and bought-in materials means that the pay-back time on the whole plant modification will only be a matter of a few months".